Rotary feed member



Aug. 19, 1924.

I H. MUELLER ROTARY FEED MEMBER Original Filed Jan 26, 1923 3 Sheets-Sheet l INVENTOR Win44;

Aug. 19, 1924. 1,505,723

H. MUELLER ROTARY FEED MEMBER.

' Original Filed Jan. 26, 1923 3 Sheets-Sheet 2 3 .lQv 6 q 4 w.

Aug. 19, 1924.

H. MUELLER ROTARY FEED MEMBER Original Filed Jan. 26. 1925 3 Sheets-Sheet 5 INVENTOR atent Aug. 19, 1924.

,mrso STATES: PATENT OFFICE.

. HENRY nunnnna, or rrr'rsnuaen,

rmmsnvam, assmnoa mo UNITED ENGINEERING & FOUNDRY (70., F PITTSBURGH, PENNSYLVANIA, A. CORPORA- TION OF PENNSYLVANIA,

Ofiginal application filed January 26, 1928, Serial No. 614,961. Divided and 18, 1924. Serial No. 700,125.

' To allv whom it may comm:

citizen of the United States, residing at Pittsburgh, county of Allegheny, and State of Pennsylvania, have invented a new and useful Improvement in Rotary Feed Members, ofwhich the following is' a full, clear, and exact description.

The present invention relates, broadly,to

lothe art of pulverized fuel feed, and more particularly to rotary feed regulators-for fuel feeding apparatus, this application being a division of my co-pending application, Serial-No. 614,961, filed January 26,

Ithas heretofore been proposedto feed pulverized fuel by means of a single screwconveyor. The difiiculty with such con:-

' structions-has been the lack of uniformity of feed andthe tendency of the fuel to continue to flow after the conveyor was stopped,

due to the fact that the single screw-conveyor offered a continuous passage forthe finely divided :fuel; This tendency ,of the @5 fuel to. vfeed unevenly and to continue to flow after the stoppage of the conveyor often produced what is. known in the art as flushing.- Toovercome this disadvantage of thesingle screw-conveyor, it has been proposed to provide apair of cooperating screws. This-type of feeder, however, has

been found in actual practice to ofier numerous disadvantages, such as rapid wearing of the 'parts', due to the constant grind ing action ofone screw upon the other, and relativelylarge power consumption, due to the necessity for rotating the screws at a relatively high. s eed while overcoming a large amount off ictional resistance; Bythe present invention the above men'- tioned and other disadvantages of the prior art constructions. are overcome, an important object of the invention being to provide a'" fuel feeding system having a single rotating'feedin'g member provided with peripheral fuelreceiving means adapted to continuously. and uniformly receive and'dis- I charge fuel with no' tendency to flushing.

A further object" of the invention is to 0' rovide a construction in which the fuel .eeding member may be rotated at slow Be it known that I, HENRY MUELLER, a-

" au-xiliary and main air conduits.

' norm? ram 7 mm m.-

fuel feeding apparatus iii-elevation, a por-.

tionof the furnace being shown. in section.

Fi rotating feeding member and of the means for conveying the fuel to and fromsaid member, and also showing the driving connections for said. member.

Figure 3 is a sectional view taken on the line IH-III' of Figure Z'and looking towards the right.

Figure 4 is a plan view of the rotatable i feeding drum.

Figure 5 is-a fragmentary sectional view feedlng mem er adapt-' re2 is a vertical sectional view of the this application filed larch showing the flexible connection between the Figure ,6 is a detail view of he flexible diaphragm formingpart of the connection shown in Figure 5,

Referring to the drawings, lindicates a housing or casing having a hopper 2 connected with a fuel feeding chute 3. Journaled .in suitable bearings in the casing 1 is a shaft 4 upon WhlCh lS mounted a drum 5. The drum 5 is fixed to the shaft 4' by meansof an integral projection 6 on the drumcooperating with a cut-away or faceted portion 7 of-the shaft, so that the drum andshaft are afixed to each other against either relative rotational on, longitudinal movement.- U f -The ends ofthe drum 5 cooperatewith bearings 8 formed integral with the lower end of the hopper 2, and in order to counteract the tendency of the pulverized material which'works in between theends of thedrum and its hearings to'- grind away the bearin and ends ofthe drum,-'the latter are eac provided with a plurality. of Independent peripheral grooves 9. Each'bearinz. 8 enioo gages only a portion of the periphery of the corresponding end of the drum, the constructlon bein such that any of the pulverized fuel which finds its way into the grooves 9 at the upper side of the drum will simply be carried around in the rotation of the drumand escape at the discharge sideof the drum. In this manner the grinding action of said material uponthe bearings and ends of the drum is reduced to a minimum. I j

The drum 5, instead of being provided with a single continuous groove, as in the ordinary screw-conveyor, is provided in its peripheral surface with a series of independent grooves 10 which extendlongitudinally of the drum, but in a direction diagonal to. its axis. It will be seen that, with this construction, as the drum rotates, each independent groove 10 will be gradually filled from end to end with material from the hopper, and then, in the further rotation of the drum, will gradually empty its load at the discharge side of the drum, whereas, if the grooves were arranged parallel .to the axis of the'drum, each groove would be filled simultaneously from end to end with material from the hopper and would discharge its entire load at substantially the same instant.

The present construction, therefore, insures a substantially uniform feeding of the material from the hopper into the air line and obviates any danger of flushing. Moreover, the provision of the independent diagonally arranged grooves prevents flushing when' the rotation of the drum is stripped.

wing to the relatively large peripheral area of the feeding drum with its series of independent grooves, the said drum can be rotated at a comparatively low speed, therewith a hollow coupling member 17.

by enabling a small power consumption. For driving the drum, a small electric motor 11 is provided, which is attached to one end of the casing 1, as indicated in Figure 2, and drives the drum through the pinion 12, gear 13, pinion 14 and gear 15. l The main air supply conduit is represented by the reference numeral 16. The conduit 9 16 communicates at its lower end burner 18 is connected at one end to an end of the coupling member 17, and at its other end projects into the opening 19 in a wall of the. furnace 20.

Branching off from the main conduit 16 at the point 21 is an auxiliary air conduit 22. This auxiliary air conduit 22 includes a section 23 of the housing 1 arranged to carry the auxiliary air supply past and in contact with the discharge side of the rotatable drum 5 and in a direction parallel to the axis of the drum. The section 23 is provided with a cleaning opening closed by a screw plug 24. A suitable valve 25 is provided in ther the conduit 22 for regulating'the auxiliary air supply.

The section 23 thereof an integral flange 26, and clamped between this flange 26 and a ring 27 by means of bolts 28 is an annular metal diaphragm 29. The peripheral edge portion of the diaphragm 29 is clamped between a flange 30 formed integral with one end of the coupling member 17 and a ring 31 secured to the flange 30 by bolts 32, a packing member 33 being interposed between the ring 31 and diaphragm 29. Threadedly connected at one end to the ring 27 and projecting'into the coupling member 17 is a pipe 34 forming an extension of the-conduit 22. The construction just described provides a flexible and adjustable connection between the main air conduit and the discharge end of the auxiliary air conduit, so as to take care of any slight inaccuracies of alinement between the fuel feeding apparatus and the furnace. When it is desired to adjust the discharge end of the auxiliary conduit with respect to the main air conduit, this can be done by loosening the nuts on the bolts 32 so as to permit shifting of the diaphragm 29 in its own plane, after which the nuts will be tightened again.

In the operation of the apparatus,'the inferentially of the drum through a relatively small arc, namely, less than 90. Since the auxiliary air supply sweeps past the drum in a direction substantially parallel to the length of the grooves, the tendency of the auxiliary air supply is to cleanthe grooves of fuel and supply them with air, which is carried around in the grooves to aerate the fuel in the hopper. By reason, of the fact that the discharge end of the auxiliary conduit 22 projects into the coupling member 17 the main air supply has an e ector action upon the auxiliary air supply and the fuel carried in suspension therein, thereby furinsuring against flushing. The grooves 9 in the end portions of the drum prevent pulverized material which may work in between the end portions of the drum and ings and the end I claim:

1. In apparatus for feeding pulverized fuel, a rotatable feeding member, means for supplying fuel to said member, and bearings for the end portions of said members, said bearings engaging said end portions throughout a portion only of the peripheral surfaces portions of the drum.

\ of the latter, said end portions each being has formed at one end formed with a circumferential groove therein, said grooves being adapted to receive pulverized fuel working in-between the end portions of the member and the-bearings and to discharge such fuel at the discharge side of the member, substantially as described.

2. In apparatus for feeding pulverized fuel, arotatable feeding member, means for supplying fuel to said member, and bearings for the end portions of said member, said bearings engaging said end portions throughout a portion only of the peripheral surfaces of the latter, said end portions each being provided With a plurality of circumferential grooves therein, said grooves being adapted to receive pulverized fuel Working in between the end portions of the'member and the bearings and to discharge such fuel at the discharge side of the member, substantially as described. I

3. As an article of manufacture, a fuel feeding drum having a plurality of independent peripheral fuel receiving recesses extending longitudinally and circumferentially thereof, and bearing portions at the ends of said drum, said bearing portions having fuel conducting recesses therein out of communication with said fuel receiving recesses and confined to said bearing portions, substantially as described.

4. As an article of manufacture, a fuel feeding drum having a plurality of independent peripheral fuel receiving recesses extending longitudinally and circumferentially thereof, and bearing portions at the ends of said drum, said bearing portions having fuel conducting recesses therein extending circumferentially thereof, and confined to said bearing portions, substantially as described.

5. In apparatus for feeding pulverized fuel, a rotatable feeding member having a plurality of independent peripheral fuel receiving grooves each extending substantially the full length of the drum and circumferentially thereof less than 180, means for supplying fuel to said member, and bearings for the end portions of said member beyond the ends of the fuel receiving grooves, said end portions having peripheral fuel conducting recesses confined to said bearings but thereby, substantially as described.

In testimony whereof I have hereunto set my hand.

HENRY MUELLER.

substantially unobstructed. 

